1. Field of the Disclosure
Embodiments of the present disclosure generally relate to an apparatus and method to lift and secure equipment to the surface of a supply vessel deck. More specifically, embodiments of the present disclosure relate to an apparatus and method to install, secure, and fill material storage units on a supply vessel deck.
2. Background Art
In the drilling of wells, a drill bit is used to dig many thousands of feet into the earth's crust. Oil rigs typically employ a derrick that extends above the well drilling platform or deck. The derrick supports joint after joint of drill pipe connected end-to-end during the drilling operation. As the drill bit is pushed further into the earth, additional pipe joints are added to the ever lengthening “string” or “drill string”. Therefore, the drill string typically includes a plurality of joints of pipe.
Fluid “drilling mud” is pumped from the well drilling platform, through the drill string, and to a drill bit supported at the lower or distal end of the drill string. The drilling mud lubricates the drill bit and carries away well cuttings generated by the drill bit as it digs deeper. The cuttings are carried in a return flow stream of drilling mud through the well annulus and back to the well drilling platform at the earth's surface. When the drilling mud reaches the platform, it is contaminated with small pieces of shale and rock that are known in the industry as well cuttings or drill cuttings. Once the drill cuttings, drilling mud, and other waste reach the platform, a “shale shaker” is typically used to remove the drilling mud from the drill cuttings so that the drilling mud may be reused. The remaining drill cuttings, waste, and residual drilling mud are then transferred to a holding trough or vessel for disposal. The drill cuttings are typically stored in large tanks or vessels on the drilling rig platform. These vessels may be large in size, and therefore, may require large spaces on the drilling rig. In some situations, for example with specific types of drilling mud, the drilling mud may not be reused and it must also be disposed. Typically, the non-recycled drilling mud is disposed of separate from the drill cuttings and other waste by transporting the drilling mud via a vessel to a disposal site.
The disposal of the drill cuttings and drilling mud is a complex environmental problem. Drill cuttings contain not only the residual drilling mud product that would contaminate the surrounding environment, but may also contain oil and other waste that is particularly hazardous to the environment, especially when drilling in a marine environment. Traditional methods of disposal include dumping, bucket transport, cumbersome conveyor belts, screw conveyors, and washing techniques that require large amounts of water. Adding water creates additional problems such as added volume, bulk, and transportation. Installing conveyors requires major modification to the rig area and involves extensive installation hours and expense.
Another method of disposal includes returning the drill cuttings, drilling mud, and/or other waste via injection under high pressure into an earth formation. Generally, the injection process involves preparation of a slurry within surface-based equipment and pumping the slurry into a well that extends relatively deep underground into a receiving stratum or adequate formation. Material to be injected back into a formation may be prepared into a slurry acceptable to high pressure pumps used in pumping material down a well. The particles are usually not uniform in size and density, thus making the slurrification process complex. If the slurry is not the correct density, the slurry often plugs circulating pumps. The abrasiveness of the material particles may also abrade or damage the pump impellers causing cracking. Some centrifugal pumps may be used for grinding the injection particles by purposely causing pump cavitations.
In some instances, the cuttings, which are still contaminated with some oil, are transported from a drilling rig to an offshore rig or ashore in the form of a thick heavy paste for injection into an earth formation. Typically, the material is transferred into special skips of about 10 ton capacity which are loaded by crane from the rig onto supply boats. This is a difficult and dangerous operation that may be laborious and expensive.
Further, space on offshore platforms may be limited. In addition to the storage and transfer of cuttings, many additional operations take place on a drilling rig, including tank cleaning, slurrification operations, drilling, chemical treatment operations, raw material storage, mud preparation, mud recycle, mud separations, and many others. Due to the limited space, it is common to modularize these operations and to swap out modules when not needed or when space is needed for the equipment. For example, cuttings containers may be offloaded from the rig to make room for modularized equipment used for tank cleaning operations.
In other drilling operations, cuttings containers may be offloaded from the rig to make room for environmental and/or drilling fluid recycling systems. Such systems may include a number of mixing, flocculating, and storage tanks to clean industrial wastewater produced during drilling or shipping operations. Slurrification systems that may be moved onto a rig are typically large modules that are fully self-contained, receiving cuttings from a drilling rig's fluid/mud recovery system.
The lifting operations required to swap modular systems, as mentioned above, may be difficult, dangerous, and expensive. Additionally, many of these modularized operations are self-contained, and therefore include redundant equipment, such as pumps, valves, and tanks or storage units.
Accordingly, there exists a continuing need for systems and methods for efficiently storing and transporting materials used in drilling operations.